1. Adams SN, Matsimela N. Feeding children with autism in South Africa: The teachers’ perspectives. African journal of disability. 2023; 12: 1252.

BACKGROUND: Over 80% of children diagnosed with autism spectrum disorders (autism) exhibit disruptive behaviours during mealtimes, highlighting the need for personalised care. In South Africa, teachers often take on the responsibility of feeding due to resource constraints and the time children spend at school. Moreover, children with autism have unique and individualised feeding requirements, which many teachers may not have the necessary training or skills to address adequately. OBJECTIVES: To explore the ways in which teachers of autistic children manage feeding difficulties in the classroom. METHOD: A qualitative research design was employed using semi-structured interviews. Eight teachers were interviewed on feeding autistic children between the ages of 3 years – 9 years in Johannesburg, South Africa. Data were transcribed and analysed using thematic analysis. RESULTS: The findings revealed that teachers encountered distinct challenges when it came to feeding autistic children in the classroom, particularly concerning the management of associated feeding difficulties. Teachers employed several strategies to encourage eating in the classroom setting including: (1) bolus modification, (2) behaviour modelling, (3) positive reinforcement and (4) offering choices and alternatives. CONCLUSION: The study concludes the need for specialised support and training for teachers to address the individualised feeding needs of children with autism. Implementing targeted interventions and providing resources for teachers could enhance their abilities to effectively support children with autism during mealtimes and promote a more inclusive classroom environment. CONTRIBUTION: This study highlighted the importance of including the teacher in the multidisciplinary team when managing the feeding challenges in children with autism.

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2. D’Mello SR. Rett and Rett-related disorders: Common mechanisms for shared symptoms?. Experimental biology and medicine (Maywood, NJ). 2023: 15353702231209419.

Rett syndrome is a neurodevelopmental disorder caused by loss-of-function mutations in the methyl-CpG binding protein-2 (MeCP2) gene that is characterized by epilepsy, intellectual disability, autistic features, speech deficits, and sleep and breathing abnormalities. Neurologically, patients with all three disorders display microcephaly, aberrant dendritic morphology, reduced spine density, and an imbalance of excitatory/inhibitory signaling. Loss-of-function mutations in the cyclin-dependent kinase-like 5 (CDKL5) and FOXG1 genes also cause similar behavioral and neurobiological defects and were referred to as congenital or variant Rett syndrome. The relatively recent realization that CDKL5 deficiency disorder (CDD), FOXG1 syndrome, and Rett syndrome are distinct neurodevelopmental disorders with some distinctive features have resulted in separate focus being placed on each disorder with the assumption that distinct molecular mechanisms underlie their pathogenesis. However, given that many of the core symptoms and neurological features are shared, it is likely that the disorders share some critical molecular underpinnings. This review discusses the possibility that deregulation of common molecules in neurons and astrocytes plays a central role in key behavioral and neurological abnormalities in all three disorders. These include KCC2, a chloride transporter, vGlut1, a vesicular glutamate transporter, GluD1, an orphan-glutamate receptor subunit, and PSD-95, a postsynaptic scaffolding protein. We propose that reduced expression or activity of KCC2, vGlut1, PSD-95, and AKT, along with increased expression of GluD1, is involved in the excitatory/inhibitory that represents a key aspect in all three disorders. In addition, astrocyte-derived brain-derived neurotrophic factor (BDNF), insulin-like growth factor 1 (IGF-1), and inflammatory cytokines likely affect the expression and functioning of these molecules resulting in disease-associated abnormalities.

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3. Duarte-Campos JF, Vázquez-Moreno CN, Martínez-Marcial M, Chavarría A, Ramírez-Carreto RJ, Velasco Velázquez MA, De La Fuente-Granada M, González-Arenas A. Changes in neuroinflammatory markers and microglial density in the hippocampus and prefrontal cortex of the C58/J mouse model of autism. The European journal of neuroscience. 2023.

Autism spectrum disorder (ASD) is a diverse group of neurodevelopmental conditions with complex origins. Individuals with ASD present various neurobiological abnormalities, including an altered immune response in the central nervous system and other tissues. Animal models like the C58/J inbred mouse strain are used to study biological characteristics of ASD. This strain is considered an idiopathic autism model because of its demonstrated reduced social preference and repetitive behaviours. Notably, C58/J mice exhibit alterations in dendritic arbour complexity, density and dendritic spines maturation in the hippocampus and prefrontal cortex (PFC), but inflammatory-related changes have not been explored in these mice. In this study, we investigated proinflammatory markers in the hippocampus and PFC of adult male C58/J mice. We discovered elevated levels of interferon gamma (IFN-γ) and monocyte chemoattractant protein 1 (MCP-1) in the hippocampus, suggesting increased inflammation, alongside a reduction in the anti-inflammatory enzyme arginase 1 (ARG1). Conversely, the PFC displayed reduced levels of TNF-α and MCP-1. Microglial analysis revealed higher levels of transmembrane protein 119 (TMEM119) and increased microglial density in a region-specific manner of the autistic-like mice, particularly in the PFC and hippocampus. Additionally, an augmented expression of the fractalkine receptor CX3CR1 was observed in the hippocampus and PFC of C58/J mice. Microglial morphological analysis shows no evident changes in the hippocampus of mice with autistic-like behaviours versus wild-type strain. These region-specific changes can contribute to modulate processes like inflammation or synaptic pruning in the C58/J mouse model of idiopathic autism.

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4. Jiang M, Wang Z, Lu T, Li X, Yang K, Zhao L, Zhang D, Li J, Wang L. Integrative analysis of long noncoding RNAs dysregulation and synapse-associated ceRNA regulatory axes in autism. Translational psychiatry. 2023; 13(1): 375.

Autism spectrum disorder (ASD) is a complex disorder of neurodevelopment, the function of long noncoding RNA (lncRNA) in ASD remains essentially unknown. In the present study, gene networks were used to explore the ASD disease mechanisms integrating multiple data types (for example, RNA expression, whole-exome sequencing signals, weighted gene co-expression network analysis, and protein-protein interaction) and datasets (five human postmortem datasets). A total of 388 lncRNAs and five co-expression modules were found to be altered in ASD. The downregulated co-expression M4 module was significantly correlated with ASD, enriched with autism susceptibility genes and synaptic signaling. Integrating lncRNAs from the M4 module and microRNA (miRNA) dysregulation data from the literature identified competing endogenous RNA (ceRNA) network. We identified the downregulated mRNAs that interact with miRNAs by the miRTarBase, miRDB, and TargetScan databases. Our analysis reveals that MIR600HG was downregulated in multiple brain tissue datasets and was closely associated with 9 autism-susceptible miRNAs in the ceRNA network. MIR600HG and target mRNAs (EPHA4, MOAP1, MAP3K9, STXBP1, PRKCE, and SCAMP5) were downregulated in the peripheral blood by quantitative reverse transcription polymerase chain reaction analysis (false discovery rate <0.05). Subsequently, we assessed the role of lncRNA dysregulation in altered mRNA levels. Experimental verification showed that some synapse-associated mRNAs were downregulated after the MIR600HG knockdown. BrainSpan project showed that the expression patterns of MIR600HG (primate-specific lncRNA) and synapse-associated mRNA were similar in different human brain regions and at different stages of development. A combination of support vector machine and random forest machine learning algorithms retrieved the marker gene for ASD in the ceRNA network, and the area under the curve of the diagnostic nomogram was 0.851. In conclusion, dysregulation of MIR600HG, a novel specific lncRNA associated with ASD, is responsible for the ASD-associated miRNA-mRNA axes, thereby potentially regulating synaptogenesis.

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5. Sapey-Triomphe LA, Sanchez G, Hénaff MA, Sonié S, Schmitz C, Mattout J. Disentangling sensory precision and prior expectation of change in autism during tactile discrimination. NPJ science of learning. 2023; 8(1): 54.

Predictive coding theories suggest that core symptoms in autism spectrum disorders (ASD) may stem from atypical mechanisms of perceptual inference (i.e., inferring the hidden causes of sensations). Specifically, there would be an imbalance in the precision or weight ascribed to sensory inputs relative to prior expectations. Using three tactile behavioral tasks and computational modeling, we specifically targeted the implicit dynamics of sensory adaptation and perceptual learning in ASD. Participants were neurotypical and autistic adults without intellectual disability. In Experiment I, tactile detection thresholds and adaptation effects were measured to assess sensory precision. Experiments II and III relied on two-alternative forced choice tasks designed to elicit a time-order effect, where prior knowledge biases perceptual decisions. Our results suggest a subtler explanation than a simple imbalance in the prior/sensory weights, having to do with the dynamic nature of perception, that is the adjustment of precision weights to context. Compared to neurotypicals, autistic adults showed no difference in average performance and sensory sensitivity. Both groups managed to implicitly learn and adjust a prior that biased their perception. However, depending on the context, autistic participants showed no, normal or slower adaptation, a phenomenon that computational modeling of trial-to-trial responses helped us to associate with a higher expectation for sameness in ASD, and to dissociate from another observed robust difference in terms of response bias. These results point to atypical perceptual learning rather than altered perceptual inference per se, calling for further empirical and computational studies to refine the current predictive coding theories of ASD.

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6. Suen YN, Chau APY, Wong SMY, Hui CLM, Chan SKW, Lee EHM, Wong MTH, Chen EYH. Comorbidity of autism spectrum and attention deficit/hyperactivity disorder symptoms and their associations with 1-year mental health outcomes in adolescents and young adults. Psychiatry research. 2023; 331: 115657.

Autism spectrum (ASD) and attention deficit/hyperactivity disorders (ADHD) share genetic, neurological, and behavioural features. However, related research in Asia is limited. We collected self-reported ASD and ADHD symptoms from 2186 Hong Kong adolescents and young adults aged 15-24 years, among whom, 1200 provided 1-year data on mental health-related outcomes. Comparative and network analyses were performed. Rating scale cutoff scores were used to divide participants into ASD, ADHD, comorbid, and control groups. The prevalence rates of ASD, ADHD, and comorbidities in Hong Kong were 13.3 %, 10.6 %, and 2.7 %, respectively. Compared with the control group, the comorbid group experienced more psychotic-like experiences (PLEs), the ASD group had poorer functioning, and the ADHD group had higher depression and anxiety symptoms and a lower quality of life after 1 year. The ability to switch attention, preference for routines and difficulty with change, and problems with organisation and planning were positively associated with depressive symptoms, forgetfulness and working memory issues with anxiety symptoms, and heightened sensory input and difficulties in sustaining attention and task completion with PLEs after 1 year. Our findings provide insight into support strategies to address the needs of young Asians to improving their well-being and long-term outcomes.

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7. Wang S, Wang B, Drury V, Drake S, Sun N, Alkhairo H, Arbelaez J, Duhn C, Bal VH, Langley K, Martin J, Hoekstra PJ, Dietrich A, Xing J, Heiman GA, Tischfield JA, Fernandez TV, Owen MJ, O’Donovan MC, Thapar A, State MW, Willsey AJ. Rare X-linked variants carry predominantly male risk in autism, Tourette syndrome, and ADHD. Nature communications. 2023; 14(1): 8077.

Autism spectrum disorder (ASD), Tourette syndrome (TS), and attention-deficit/hyperactivity disorder (ADHD) display strong male sex bias, due to a combination of genetic and biological factors, as well as selective ascertainment. While the hemizygous nature of chromosome X (Chr X) in males has long been postulated as a key point of « male vulnerability », rare genetic variation on this chromosome has not been systematically characterized in large-scale whole exome sequencing studies of « idiopathic » ASD, TS, and ADHD. Here, we take advantage of informative recombinations in simplex ASD families to pinpoint risk-enriched regions on Chr X, within which rare maternally-inherited damaging variants carry substantial risk in males with ASD. We then apply a modified transmission disequilibrium test to 13,052 ASD probands and identify a novel high confidence ASD risk gene at exome-wide significance (MAGEC3). Finally, we observe that rare damaging variants within these risk regions carry similar effect sizes in males with TS or ADHD, further clarifying genetic mechanisms underlying male vulnerability in multiple neurodevelopmental disorders that can be exploited for systematic gene discovery.

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